Welcome to Bimmerfest -- The #1 Online Community for BMW related information! Please enjoy the discussion forums below and share your experiences with the 200,000 current, new and past BMW owners. The forums are broken out by car model and into other special interest sections such as BMW European Delivery and a special forum to voice your questions to the many BMW dealers on the site to assist our members!

I want to drain the coolant from the engine (99 M Coupe) but the O2 sensor seems to block access. Getting a open end wrench on the plug is no problem...but unless it's a short plug I'm going to run into the sensor before the plug is free...something I don't want to do.

I've tackled this before. It's a little difficult getting in there, but as I recall I only used some standard Craftsman tools with not too much trouble. Sorry I can't be more helpful, it's been a while since I've done this job.